
People have claimed that kola nut sweetens stale water, treats fatigue, and eases hunger pains. Now, experts in a new study say that its consumption in high amounts and over a long period of time can impair memory, learning and emotions.
In animal studies, researchers found that high dose and long-term consumption of kola nut extract easily alters and modifies the subtle chemical and electrical processes of the brain, deterring the birth of new neurons in the brain and the functioning of the hippocampus.

It was in the 2023 journal, Phytomedicine Plus.
The hippocampus is the region of the brain that is associated primarily with memory. It is thought to be principally involved in storing long-term memories and in making those memories resistant to forgetting, though this is a matter of debate.
The hippocampus is also susceptible to damage from injury, stress and disease, including psychiatric and neurological conditions such as Alzheimer’s, schizophrenia, and depression.
Over the years, the consumption of kola nut in several parts of the world has increased considerably, and many are unaware of the side effects of its continuous usage or excessive use.
Also many studies have documented the role of kolanut on brain structures.
The use of various psychoactive substances can easily alter and modify the subtle chemical and electrical processes of the brain. Hence this study analyzed the effect of varying doses and duration of kola nut extract (KNE) on form and structure of the hippocampus, as well as learning and memory.
The study included 50 albino mice that were divided into five groups of ten mice each. Group 1 received 3.3 mg/kg of extract for 10days, Group 2 received 2.84 mg/kg of extract for 7days, Group 3 received 2.45 mg/kg of extract for 5days, Group 4 received 2.73 mg/kg of extract for 3days, Group 5 were treated with 5 ml/kg of distilled water for 10days.
This study revealed gradual structural changes with prolonged use of kola nut. In group 3 and 4, there were no viable changes in the structure of the hippocampus. In contrast, group 1 and 2 show marked changes in its structural components.
Also observed was an increase in weight of the experimental groups, except in group 3. The active constituent in kola nut (caffeine) may possess appetite-suppressant effects and this effect produces weight loss in habitual users.
Kola nut has been consumed in West African countries for ages now, and there is no doubt it has incredible uses and benefits. But on the other hand, there are dangerous side effects. Chewing kola nuts constantly has a higher tendency to increase the risk of mouth cancer and gastrointestinal cancer.
Also, due to its caffeine content, large amounts of kola nut might cause headache, anxiety, agitation, ringing in the ears, and irregular heartbeats. Stopping the use of caffeine suddenly can sometimes result in headaches, irritation, nervousness, anxiety, and dizziness.
Kola nut contains caffeine, which might slow blood clotting. This makes some experts worry that kola nut might make bleeding disorders worse. Also, caffeine in kola nut might cause irregular heartbeat in certain people, thus the need for caution by individuals with a heart condition.
Medical practitioners have advised people with diabetes not to consume kola nuts as it may worsen the ailment. Some research suggests that caffeine may affect the way the body uses sugar and might worsen diabetes.
In addition, excessive kola nuts are not safe for pregnant mothers and their unborn babies. It might increase the chance of miscarriage, early delivery, and low birth weight.